CN111490629A

CN111490629A - Electric machine and method for producing an electric machine

Info

Publication number: CN111490629A
Application number: CN202010075209.XA
Authority: CN
Inventors: 布兰得利·赫弗
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2019-01-29
Filing date: 2020-01-22
Publication date: 2020-08-04
Also published as: US10821819B2; DE102020102041A1; US20200238813A1

Abstract

The present disclosure provides "electric machines and methods for manufacturing electric machines. A drivetrain system having an electric machine and a method for manufacturing a drivetrain system are provided to achieve increased coupling strength between a rotor support, a rotor drive hub and a rotor. The drive train system includes the rotor drive hub axially sandwiched between a portion of the rotor spider and a plurality of stacked rotor portions. The drivetrain system also includes a torque converter drive plate coupled to the rotor drive hub and a torque converter.

Description

Electric machine and method for producing an electric machine

Technical Field

The present invention generally relates to an electric machine in a drive train system and a method for manufacturing an electric machine.

Background

Hybrid vehicles have incorporated an electric motor directly coupled to a torque converter to allow efficient introduction of rotational output from the electric motor into the vehicle driveline. In previous electric motor designs, portions of the rotor in the motor were directly screw coupled or riveted to the torque converter housing.

One exemplary method is shown in U.S.7,509,802 to Hammond et al. The Hammond system uses bolts to attach the disc member of the rotor assembly to the housing of the torque converter. However, the inventors herein have recognized potential issues with such systems. For example, bolting the rotor directly to the torque converter housing requires a complex manufacturing process. Further, the interface between the torque converter housing and the rotor is formed at an early stage of the manufacturing process of the electric motor. For example, the rotor may be riveted to the torque converter housing prior to welding the portions of the torque converter housing together. As a result, the cost of motor manufacture is increased and the flexibility of the manufacturing process is reduced.

Disclosure of Invention

In one example, the above-described problem may be at least partially solved by an electric machine. The motor includes: a rotor including a plurality of laminated rotor portions; a rotor support; a torque converter drive plate coupled to the rotor drive hub; and a torque converter coupled to the torque converter drive plate. The rotor drive hub is axially sandwiched between the rotor support and the plurality of stacked rotor sections. In this manner, the rotor is operatively coupled to the torque converter via a clamping engagement. It should also be appreciated that the rotor, the rotor drive hub and the rotor support may be clamped late in the manufacturing process (e.g., after welding the torque converter housing), if desired, thereby improving the flexibility of the manufacturing process of the electric machine.

In one example, a splined interface may be formed between the rotor drive hub and the rotor support. In this way, the strength of the attachment between the rotor drive hub and the rotor support may be increased. The increased attachment strength may result in smoother operation and more robust motors.

It should be appreciated that the summary above is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Drawings

Fig. 1 shows a schematic view of a vehicle comprising an electric machine and an internal combustion engine.

Fig. 2 shows an example of the electric machine shown in fig. 1.

Fig. 3 shows a detailed view of a portion of the motor shown in fig. 2.

Fig. 4 shows another detailed example of the motor shown in fig. 1.

Fig. 5 shows an example of a spline interface that may be included in the electric machine depicted in fig. 2-4.

Fig. 6 shows an example of a key interface that may be included in the electric machine depicted in fig. 2-4.

Fig. 7 shows a method for manufacturing an electric machine.

Fig. 1 to 4 are generally drawn to scale. However, in other embodiments, other relative dimensions may be used.

Detailed Description

The following description relates to an electric machine having a rotor drive hub clamped between the rotor and a rotor support. The insertion of the rotor drive hub between the rotor support and the rotor allows for a robust and easy connection between the rotor drive hub and the rotor support, compared to electric motors where the rotor is riveted to the rotor support. Furthermore, if desired, the clamping interface in the motor may be formed at a later stage of the manufacturing process compared to previous manufacturing methods. Therefore, the adaptability of the manufacturing process is improved, and the manufacturing cost of the motor is reduced. In one example, a splined interface may be formed between the rotor drive hub and the rotor support, further increasing the strength of the interface formed between the hub and the support. Therefore, the motor can be operated more smoothly. It should also be appreciated that the splined interface may simplify the manufacturing process of the electric machine as compared to an electric motor in which the rotor components are riveted directly to the torque converter.

FIG. 1 shows a schematic view of a vehicle with a propulsion system having an electric machine. Fig. 2 shows a first embodiment of an electric machine with a torque converter having a rotor drive hub axially interposed between a rotor carrier and a rotor. Fig. 3 shows a detailed view of the clamping portion of the motor shown in fig. 1. Fig. 4 shows a second embodiment of an electric machine with a torque converter that axially clamps a rotor drive hub with a rotor carrier and a rotor. Fig. 5 shows an example of a spline interface in the embodiment in the electrical machine shown in fig. 2-4. Fig. 6 shows an example of a key interface in the embodiment in the electrical machine shown in fig. 2-4. Fig. 7 shows an example of an in-line manufacturing method for a motor.

Referring to FIG. 1, a vehicle 10 having a propulsion system 11 (e.g., a hybrid propulsion system) is schematically depicted. Propulsion system 11 includes an internal combustion engine 12. The internal combustion engine 12 is coupled to an electric machine 14 (e.g., an energy conversion device).

The electric machine 14 is further shown coupled to an energy storage device 16, which may include a battery, a capacitor, a flywheel, a pressure vessel, and the like. The electric machine 14 may be operable to absorb energy from vehicle motion and/or the engine and convert the absorbed energy into a form of energy suitable for storage by the energy storage device (e.g., to provide generator operation). The electric machine 14 may also be operable to supply output (power, work, torque, rotational speed, etc.) to the drive wheels 18 and/or the engine 12 (e.g., to provide motor operation). It should be appreciated that, in some embodiments, the electric machine 14 may function as a motor only, a generator only, or both in addition to various other components for providing suitable energy conversion between the energy storage device and the vehicle drive wheels and/or engine. For example, the electric machine 14 may include a motor, a generator, an integrated starter generator, a starter generator, and the like, as well as combinations thereof.

The energy storage device 16 may be selectively coupled to an external energy source 19. For example, the energy storage device 16 may be periodically coupled to a charging station (e.g., a commercial or residential charging station), a portable energy storage device, or the like, to allow the energy storage device 16 to be recharged.

The electric machine 14 is coupled to a torque converter 20. The torque converter 20 is a fluid coupling designed to transmit rotational input from the electric machine 14 and/or the internal combustion engine 12 to the driveline 22. The drive train 22 includes a transmission having a gear assembly and other suitable mechanical components designed to transmit rotational motion to the drive wheels 18. The mechanical components may include, for example, a gearbox, axle, transfer case, etc. The torque converter 20 and the electric machine 14 are depicted as interconnected units. However, in other examples, the torque converter and the electric machine may include separate housings.

In one example, a crankshaft of the engine may be coupled to an input of the electric machine, and a shaft of the torque converter 20 may be attached to a transmission input. However, other drive train designs have been contemplated.

The depicted connections between the engine 12, the electric machine 14, the driveline 22, and the drive wheels 18 indicate the transfer of mechanical energy from one component to another, while the connection between the electric machine 14 and the energy storage device 16 may indicate the transfer of multiple forms of energy (such as electrical, mechanical, etc.). For example, torque may be transmitted from the electric machine 14 to drive the vehicle drive wheels 18 via a driveline 22. As described above, the electric machine 14 may be configured to operate in a generator mode and/or a motor mode. In the generator mode, the system 11 absorbs some or all of the output from the engine 12 and/or the electric machine 14, which reduces the amount of drive output delivered to the drive wheels 18 or the amount of brake torque delivered to the drive wheels 18. Such operation may be employed, for example, to achieve efficiency gains through regenerative braking, increased engine efficiency, and the like. Further, the output received by the electric machine may be used to charge energy storage device 16. In the motoring mode, the electric machine 14 may supply mechanical output to the driveline 22, for example, by using electrical energy stored in a battery. Additionally, in some cases, the engine 12 may supply rotational output to the driveline 22 during the electric motor mode.

Hybrid propulsion embodiments may include a full hybrid system, wherein the vehicle may run only the engine, only the electric machine (e.g., motor), or a combination of both. An auxiliary or mild hybrid configuration may also be employed, where the engine is the primary torque source, with the hybrid propulsion system being used to selectively deliver increased torque, such as during tip-in or other conditions. Still further, starter/generator and/or smart alternator systems may also be used. The various components described above with reference to FIG. 1 may be controlled by a vehicle controller 50 as described in more detail herein.

From the foregoing, it should be appreciated that the exemplary hybrid propulsion system is capable of various operating modes. In a full hybrid embodiment, for example, the propulsion system may operate using the electric machine 14 as the only source of torque to propel the vehicle. This "electric only" mode of operation may be employed during braking, low speed, and out of service at traffic lights, etc. In another mode, the engine 12 is on and serves as the sole source of torque on the drive surface 21 to power the drive wheels 18. In yet another mode, which may be referred to as an "assist" mode, the electric machine 14 may supplement and cooperate with the torque provided by the engine 12. As indicated above, the electric machine 14 may also operate in a generator mode, wherein torque is absorbed from the engine 12 and/or the driveline 22. Further, the electric machine 14 may be used to increase or absorb torque during transitions of the engine 12 between different combustion modes (e.g., during transitions between spark ignition and compression ignition modes).

Fig. 1 also shows a controller 50 in the vehicle 10. The controller 50 receives signals from the various sensors of FIG. 1 and employs the various actuators of FIG. 1 to adjust vehicle operation based on the received signals and instructions stored in the non-transitory memory of the controller. The motors shown in fig. 2-6 may also be controlled by the vehicle controller 50. Specifically, the controller 50 is shown in fig. 1 as a conventional microcomputer including: microprocessor unit 52, input/output ports 54, read only memory 56, random access memory 58, keep alive memory 59 and a conventional data bus. Controller 50 is configured to receive various signals from sensors coupled to propulsion system 11 and send command signals to actuators in vehicle components, such as electric machine 14. In addition, the controller 50 is also configured to receive a Pedal Position (PP) from a pedal position sensor 60 coupled to a pedal 62 actuated by an operator 64. Thus, in one example, the controller 50 may receive the pedal position signal and adjust an actuator in the motor 14 based on the pedal position signal to vary the rotational output of the motor 14. It should be appreciated that other components that receive command signals from the controller (such as the engine 12) may function in a similar manner. The sensors in communication with the controller 50 may include an engine speed sensor 66, a motor speed sensor 68, an engine temperature sensor 70, and the like.

Fig. 2 shows an example of a drive train system 200 including an electric machine 202. It should be appreciated that the electric machine 202 and torque converter 204 shown in FIG. 2 serve as examples of the electric machine 14 and torque converter 20 shown in FIG. 1.

The electric machine 202 is rotationally coupled to a crankshaft 206 of the engine 12 (such as the engine shown in fig. 1). The electric machine 202 may transfer rotational energy to a drive train, such as the drive train 22 shown in fig. 1, during the drive mode. On the other hand, during the energy absorption mode, the electric machine 202 may also receive rotational energy from an engine (such as the engine 12 shown in fig. 1) and/or a drivetrain and convert the rotational energy to electrical energy.

The torque converter 204 is also shown rotationally coupled to the electric machine 202. The torque converter 204 is configured to transfer rotational energy to a downstream component (e.g., a driveline). To achieve the rotational energy transfer function, the torque converter 204 includes a hydraulic chamber (hydro chamber)208 that is closed via a housing 210 and other suitable mechanical components to achieve the rotational energy transfer. The housing 210 is shown to include portions 212 that may be welded to one another via a welded interface 214.

The electric machine 202 may include a stator 216 and a rotor 218. Stator 216 electromagnetically interacts with rotor 218 to provide the aforementioned rotational energy generation and absorption functions. Specifically, in the drive mode, the stator 216 electromagnetically interacts with the rotor 218 to drive the rotor. The axis of rotation 220 of the motor 202 is provided for reference in fig. 2 and 3. The radial axis 221 of the system is also provided for reference in fig. 2 and 3.

In the energy recovery mode, the stator 216 electromagnetically interacts with the rotor 218 to generate electrical energy in the stator 216. Accordingly, the stator 216 may transfer electrical energy to or from an energy storage device (such as the energy storage device 16 shown in fig. 1). In the depicted example, the stator 216 at least partially circumferentially encloses the rotor 218. However, other arrangements between the rotor and the stator have been envisaged.

The rotor 218 includes a plurality of stacked rotor portions 222 (e.g., axially stacked rotor portions), the stacked rotor portions 222 of the rotor 218 are clamped to a rotor bracket 224, the stacked rotor portions 222 provide the aforementioned electromagnetic interaction with the stator 216 during operation of the electric machine 202. the rotor bracket 224 serves as a rotational support for the rotor 218. to achieve a rotational function, the rotor bracket 224 is coupled to a bearing 226. in detail, in the illustrated example, the rotor bracket 224 includes a support leg 228 that is coupled to the bearing 226 to facilitate rotation of the rotor bracket. the support leg 228 includes a portion 229 that extends axially toward the axis of rotation 220 to facilitate bearing attachment.

The support legs 228 and the armature support 224 may be formed as one continuous piece to strengthen the armature support. However, in other examples, the support leg and the rotor bracket may be separate components coupled to each other. In addition, bearing 226 includes a race 230 and roller elements 232 to perform a rotational function. The roller elements may be spherical, cylindrical, conical, etc.

The rotor drive hub 234 is shown to include a portion 236 that is axially positioned between the laminated rotor portion 222 of the rotor 218 and the rotor spider 224. The body 241 of the rotor drive hub 234 extends between the hub portion 236 and the hub flange 239. A hub flange 239 forms a connection between the rotor drive hub 234 and the torque converter drive plate 238. Thus, rotor drive hub 234 is configured to transfer rotational energy from the rotor to torque converter drive plate 238. Specifically, a face 240 (e.g., a radial face) of the rotor 218 contacts a first axial side 242 of the portion 236 of the rotor drive hub 234. The face 244 (e.g., radial face) of the rotor spider 224 also contacts a second axial side 246 of the portion 236 of the rotor drive hub 234. Clamping between the rotor 218 and the rotor support 224 may be achieved via an end cap 235 coupled to an axial end 237 of the rotor 218. In one example, the assemblies may be coupled together via heating end cap 235 to an elevated temperature (which results in an increase in the inner diameter of the end cap). This substantially reduces, and in some cases substantially eliminates, the press fit between the end cap and the rotor spider 224. Continuing with the above example, after end cap 235 may be heated, the end cap may be assembled and mechanically clamped in place on rotor support 224. Additionally, the clamping force may be maintained on the end cap 235 until the cap temperature drops below the threshold and the press fit is regained. At this point, the assembly is mechanically clamped via an interference fit between the end cap 235 and the rotor spider 224. Clamping the rotor to the rotor bracket 224 (with the rotor drive hub positioned between the rotor and the rotor bracket) enables a reinforced interface to be formed between these components. Thus, in some examples, the rotor may be attached to the rotor bracket without the use of an attachment device. In this way, the manufacture of the motor can be simplified, thereby reducing manufacturing costs. Furthermore, it should be appreciated that clamping the rotor drive hub between the rotor and the rotor carrier may be performed at a manufacturing stage after assembly of the torque converter, if desired, thereby improving the flexibility of the process.

In the illustrated example, a mechanical interface 248 is formed between the rotor drive hub 234 and the rotor spider 224. The mechanical interface 248 may be a spline interface, a key interface, or the like. Examples of spline interfaces and keyed interfaces are shown in fig. 5-6 and described in more detail herein. However, in other examples, the clamping engagement between the rotor 218 and the rotor bracket 224 may be the only mechanism coupling the rotor 218, the rotor drive hub 234, and the rotor bracket 224. In such an example, the clamping force between the rotor 218 and the rotor bracket 224 may provide a directional clamping force to attach the lamination portion 222 of the rotor 218 to the rotor bracket 224.

In one example, a radial interference fit may be formed between drive plate 238 and rotor spider 224. Specifically, in one case, the radial fit of the interface between the Outer Diameter (OD) of drive plate 238 and the Inner Diameter (ID) of carrier 224 may be used as a reference for alignment. Thus, the possibility of misalignment of the drive plate with the bracket is reduced. It should be appreciated that in some examples, the angular alignment between the drive plate and the bracket may not need to be highly accurate. However, in such an example, a high degree of accuracy may be required with respect to the alignment between the centerline of the drive plate and the centerline of the rotor support. Thus, a radial interference fit between the plate and the bracket allows such centerline alignment accuracy to be achieved, if desired. It should be appreciated that in some instances, the bolt 239 may not provide the desired centerline alignment.

Fig. 2 also shows a clutch assembly 254 including clutch plates 256 configured to rotationally couple and decouple the crankshaft 206 with the rotor 218. In one particular example, the clutch assembly 254 may be an Internal Combustion Engine (ICE) disconnect clutch. However, other suitable clutch types have been contemplated. The clutch plate 256 may be engaged with the rotor bracket 224 when in driving engagement. For example, the clutch plate 256 and the rotor carrier 224 may each include splines 258 that mate with each other when the clutch assembly is drivingly engaged. However, when the clutch assembly 254 is disengaged, the clutch plates 256 may be decoupled from the rotor carrier 224. For example, when the clutch assembly 254 is disengaged, the clutch plate 256 and the splines 258 in the rotor carrier 224 may be decoupled from each other. However, other clutch configurations that allow rotor engagement/disengagement have been contemplated.

Also shown in fig. 2 is a damper assembly 260. The damper assembly 260 is designed to dampen the torque transmitted to the torque clutch in the torque converter 204. For example, fluid chambers, springs, other suitable mechanical components, and the like may be used to achieve the damping function. However, in other examples, the damper assembly may be omitted from the torque converter.

A torque converter drive plate 238 is shown in FIG. 2 as being coupled (e.g., fixedly coupled) to rotor drive hub 234 at flange 239. Accordingly, an attachment device 252 (e.g., bolts, rivets, screws, etc.) extends through the rotor drive hub 234 and the torque converter drive plate 238. In this way, a fixed attachment may be formed between the drive plate and the drive hub. In the illustrated example, the interface between the torque converter drive plate 238 and the rotor drive hub 234 is positioned axially inward relative to the torque converter 204 from an interface 248 between the rotor drive hub 234 and the rotor spider 224. Additionally, the interface between torque converter drive plate 238 and rotor drive hub 234 is positioned radially outward from an interface 248 between rotor drive hub 234 and rotor spider 224 relative to rotational axis 220. In this manner, the attachment formed between rotor drive hub 234 and torque converter drive plate 238 may be more easily accessed during assembly, maintenance, etc. As a result, the manufacture and maintenance of the motor can be further simplified. However, other relative positions of the two interfaces have been envisaged.

A torque converter drive plate 238 is coupled to the housing 210 of the torque converter 204. An attachment device 255 (e.g., a bolt, rivet, screw, etc.) extends (e.g., axially extends) through the torque converter drive plate 238 and the housing 210 of the torque converter 204. Thus, rotational energy may be transferred from the rotor 218 through the rotor carrier 224, the rotor drive hub 234, the torque converter drive plate 238, and then to the torque converter 204. The attachment device 255 is positioned radially inward from the attachment device 252 and spaced apart from the rotor bracket 224. In this manner, torque converter drive plate 238 may be attached to torque converter 204 in a space efficient manner. However, in other examples, other locations of the attachment interface between the torque converter plate and the torque converter may be used.

Fig. 3 shows a detailed view of a portion of the motor 202 depicted in fig. 2. The rotor spider 224 is shown to include a portion 300 that is circumferentially enclosed by the rotor 218 (specifically the lamination portion 222). Additionally, an outer surface 302 of the rotor spider 224 is in coplanar contact with an outer surface 304 of the lamination portion 222 of the rotor 218. In particular, a friction fit may be formed between the rotor support and the rotor. In this manner, the rotor support 224 supports the rotor 218 and substantially prevents rotational movement between the components. However, other bracket and rotor arrangements have been envisaged, such as non-press fit arrangements.

Fig. 3 again shows the clutch assembly 254 in a driving configuration, wherein the splines 258 in the assembly are engaged with the rotor support 224. Also shown is an end cap 235 coupled to rotor support 224. End cap 235 allows a compressive clamping force to be applied to rotor drive hub 234 via rotor spider 224 and rotor 218.

Fig. 4 shows another example of a drive train system 400 including an electric machine 402. The motor 402 shown in fig. 4 includes many of the structural and functional features of the motor 202 shown in fig. 2. For example, the motor 402 shown in fig. 3 again includes a rotor drive hub 404 axially sandwiched between a rotor 406 having a plurality of stacked sections and a rotor support 408. Therefore, redundant descriptions of these common features are omitted for the sake of brevity.

The motor 402 shown in fig. 4 is shown to include an end cap 410 that is threadably engaged with the rotor support 408. Specifically, end cover 410 and rotor support 408 each include threads 412 that engage one another. The threaded end cap 410 allows clamping of the laminated portion of the rotor to the rotor support. Specifically, in one example, threads on the end cap may replace the press-fit interface. By using a threaded end cap, the higher cost of the assembly equipment for heating the end cap and pressing it into place when hot can be avoided, if desired. Thus, when utilizing a threaded end cap in an electric machine, a simpler and less costly system of torquing the cap may be employed. An end cap 410 (e.g., a threaded end cap) is positioned axially outward from rotor 406. However, other threaded end cap locations have been contemplated.

Fig. 5 and 6 illustrate an example of a mechanical interface 248 between the rotor drive hub 234 and the rotor spider 224 shown in fig. 2. The cross-sectional view is taken along a radial plane of the electric machine. Thus, the viewing direction is aligned with the rotational axis of the electric machine and extends toward the torque converter 204 shown in fig. 2.

Specifically, fig. 5 shows an example of a splined interface 500 between a rotor drive hub 502 and a rotor bracket 504. The spline interface 500 includes a plurality of protrusions 506 and recesses 508 that mate with one another. It should be appreciated that protrusions and recesses are included in each of the rotor drive hub 502 and the rotor support 504. Thus, the protrusion 506 and the recess 508 have complementary shapes. It should be appreciated that the splined interface extends circumferentially about the rotational axis of the electric machine.

Fig. 6 shows an example of a keyed interface 600 between a rotor drive hub 602 and a rotor bracket 604. The keyed interface 600 includes a keyway 606 and a key protrusion 608. In the example shown, the keyway 606 is included in the rotor drive hub 602, and the key 608 is included in the rotor spider 604. However, in other examples, the situation may be reversed (i.e., the keyway may be included in the rotor spider and the key protrusion may be included in the rotor drive hub). The key 608 mates with the keyway 606 to form the interface 600. Thus, a strong and efficiently manufactured connection between the rotor drive hub and the rotor support may be formed.

The drive train system and the electric machine described in relation to fig. 1 to 6 allow a simple but robust connection to be made between the rotor support and the rotor drive hub. In addition, the mechanical coupling can be efficiently formed at a later stage of the manufacturing process of the motor to reduce the manufacturing cost of the motor.

Fig. 1 to 6 show exemplary configurations in the case of relative positioning of various components. If shown as being in direct contact or directly coupled to each other, such elements may be referred to as being in direct contact or directly coupled, respectively, at least in one example. Similarly, elements shown as abutting or adjacent to each other may be abutting or adjacent to each other, respectively, at least in one example. As one example, components placed in coplanar contact with each other may be referred to as coplanar contacts. As another example, elements that are positioned apart from one another such that there is only a space therebetween without other components may be referred to as such in at least one example. As yet another example, elements shown above/below each other, on opposite sides of each other, or on left/right sides of each other may be referred to as such with respect to each other. Further, as shown, in at least one example, the topmost element or the topmost point of an element may be referred to as the "top" of the component, and the bottommost element or the bottommost point of an element may be referred to as the "bottom" of the component. As used herein, top/bottom, upper/lower, above/below may be with respect to the vertical axis of the figure, and are used to describe the positioning of elements of the figure with respect to each other. As such, in one example, an element shown above other elements is positioned vertically above the other elements. As yet another example, the shapes of elements depicted in the figures may be referred to as having these shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, etc.). Further, in at least one example, elements shown as intersecting one another may be referred to as intersecting elements or as intersecting one another. Further, in one example, an element shown as being within another element or shown as being external to another element may be referred to as such.

Fig. 7 shows a method 700 for manufacturing a drivetrain system. The method 700 may be implemented to manufacture the driveline system, electric machine described above with respect to fig. 1-6. However, in other examples, the method may be used to manufacture other suitable drive train systems. The instructions for performing the method 700 may be executed by the controller based on instructions stored in a memory of the controller. Further, it should be apparent that the method steps may be performed at least in part via an automated tool equipment having a controller. However, in some examples, at least a portion of the method steps may be performed manually via a manufacturing person.

At 702, the method includes assembling a torque converter. Assembling the torque converter may include welding together housing portions of the torque converter. Next at 704, the method includes attaching a torque converter plate to a torque converter housing. For example, an attachment device (e.g., a bolt, a rivet, etc.) may be used to form the aforementioned attachment between the torque converter housing and the torque converter plate. In one example, the method may further comprise: the torque converter drive plate is aligned with the rotor drive hub using a radial interference fit formed between the rotor spider and the torque converter drive plate. In this way, the required alignment between the bracket and the drive plate can be established if required.

At 706, the method includes clamping the rotor support to the plurality of stacked portions in the rotor with the rotor drive hub axially positioned between a face of the rotor and a face of the rotor support. In one example, clamping the rotor support to the rotor may include mating a plurality of splines in the rotor support and the rotor drive hub. It should also be appreciated that the end caps may be threaded or otherwise attached to the ends of the rotor spider to create the clamping force. In this way, the splines, which are both clamped and mechanically engaged, may form a connection between the rotor carrier and the drive hub to increase the strength of the connection. It should also be appreciated that the steps of clamping and mating the splines may be performed efficiently during manufacture. Therefore, the manufacturing cost of the motor can be reduced.

A technical effect of providing a drive train system with a rotor drive hub axially clamped between a rotor support and a rotor is to improve the manufacturing efficiency of the drive train system and to improve the strength of the attachment between the rotor drive hub and the rotor support. As a result, the manufacturing cost of the drive train system and the possibility of rotor failure are reduced.

The invention will be further described in the following paragraphs. In one aspect, there is provided an electric machine including: a rotor comprising a plurality of stacked rotor portions; a rotor support; a rotor drive hub axially sandwiched between the rotor support and the plurality of stacked rotor portions; a torque converter drive plate coupled to the rotor drive hub; and a torque converter coupled to the torque converter drive plate.

In another aspect, a method of manufacturing an electric machine is provided, the method comprising clamping a rotor carrier to a plurality of stacked portions in a rotor after assembling a torque converter, wherein a rotor drive hub is axially positioned between a face of the rotor and a face of the rotor carrier, wherein the electric machine comprises: a torque converter drive plate coupled to the rotor drive hub; and a torque converter coupled to the torque converter drive plate. In one example, the method may further comprise: aligning the torque converter drive plate with the rotor drive hub using a radial interference fit formed between the rotor spider and the torque converter drive plate.

In any aspect or combination of aspects, assembling the torque converter can include welding portions of a torque converter housing to each other.

In any aspect or combination of aspects, clamping the rotor support to the plurality of lamination portions can include mating a plurality of splines in the rotor support and the rotor drive hub.

In any aspect or combination of aspects, the electric machine can further include a splined interface formed between the rotor drive hub and the rotor support.

In any aspect or combination of aspects, the spline interface can include a plurality of mating projections and recesses included in each of the rotor drive hub and the rotor bracket.

In any aspect or combination of aspects, the torque converter drive plate may be secured to the rotor drive hub at a location radially outward from the splined interface.

In any aspect or combination of aspects, the electric machine can further comprise a keyed interface formed between the rotor drive hub and the rotor support, wherein the keyed interface comprises a keyway that mates with a keyed protrusion.

In any aspect or combination of aspects, the electric machine can further include an end cap threaded onto the first end of the rotor support and spaced apart from the second end of the rotor support coupled to the rotor drive hub.

In any aspect or combination of aspects, the rotor support may form a continuous shape and include a support leg coupled to a rotor bearing.

In any aspect or combination of aspects, the torque converter can be coupled to a driveline.

In any aspect or combination of aspects, the drivetrain system may further comprise a spline interface formed between the rotor drive hub and the rotor support, wherein the spline interface comprises a plurality of mating protrusions and recesses included in each of the rotor drive hub and the rotor support.

In any aspect or combination of aspects, the drivetrain system can further include an end cap threaded onto the first end of the rotor support and spaced apart from the second end of the rotor support coupled to the rotor drive hub.

In any aspect or combination of aspects, the torque converter can be rotationally coupled to a drive wheel.

In any aspect or combination of aspects, the electric machine can be selectively rotationally coupled to an internal combustion engine and/or a torque converter.

In any aspect or combination of aspects, the torque converter drive plate and the rotor drive hub may be attached via a radial interference fit.

In another expression, there is provided an electric machine, comprising: an axial clamping interface formed between the laminated rotor portions; a rotor drive hub; and a rotor support coupled to the rotor bearing, wherein the rotor drive hub is attached to the torque converter via a torque converter drive plate.

In yet another representation, an electric machine is provided that includes an axial clamping assembly having rotor laminations positioned on a first axial side of a rotor drive hub and a rotor bracket flange positioned on a second axial side of the rotor drive hub opposite the first axial side, wherein the clamping assembly substantially prevents relative movement between a rotor, the rotor bracket, and the rotor drive hub.

It should be noted that the exemplary control and estimation routines included herein may be used with various engine and/or vehicle system configurations. The control methods and programs disclosed herein may be stored as executable instructions in a non-transitory memory and executed by a control system, including a controller, in conjunction with various sensors, actuators, and other engine hardware. The specific routines described herein may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various acts, operations, or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations, and/or functions may be repeatedly performed depending on the particular strategy being used. Further, the acts, operations, and/or functions may graphically represent code to be programmed into the non-transitory memory of the computer readable storage medium in the engine control system, wherein the acts are performed by executing instructions in conjunction with the electronic controller in the system including the various engine hardware components.

It will be appreciated that the configurations and routines disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. For example, the above techniques may be applied to V6 cylinders, inline 4 cylinders, inline 6 cylinders, V12 cylinders, opposed 4 cylinders, and other engine types. The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various systems and configurations, and other features, functions, and/or properties disclosed herein.

As used herein, the term "about" is considered to mean ± 5% of the range, unless otherwise indicated.

The following claims particularly point out certain combinations and subcombinations regarded as novel and nonobvious. These claims may refer to "an" element or "a first" element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.

According to the present invention, there is provided an electric motor having: a rotor comprising a plurality of stacked rotor portions; a rotor support; a rotor drive hub axially sandwiched between the rotor support and the plurality of stacked rotor portions; a torque converter drive plate coupled to the rotor drive hub; and a torque converter coupled to the torque converter drive plate.

According to one embodiment, the invention also features a splined interface formed between the rotor drive hub and the rotor support.

According to one embodiment, the spline interface comprises a plurality of mating protrusions and recesses included in each of the rotor drive hub and the rotor support.

According to one embodiment, the torque converter drive plate is secured to the rotor drive hub at a location radially outward from the splined interface.

According to one embodiment, the invention also features a keyed interface formed between the rotor drive hub and the rotor support, wherein the keyed interface includes a keyway that mates with a keyed protrusion.

According to one embodiment, the torque converter drive plate and the rotor drive hub are attached via a radial interference fit.

According to one embodiment, the electric machine is selectively rotationally coupled to an internal combustion engine and/or a torque converter.

According to one embodiment, the invention also features an end cap threadably connected to a first end of the rotor support and spaced apart from a second end of the rotor support coupled to the rotor drive hub.

According to one embodiment, the rotor support forms a continuous shape and comprises a support leg coupled to a rotor bearing.

According to one embodiment, the torque converter is coupled to a driveline.

According to the present invention, a method for manufacturing an electric machine includes: after assembling the torque converter, clamping a rotor bracket to a plurality of stacked portions in a rotor with a rotor drive hub axially positioned between a face of the rotor and a face of the rotor bracket, wherein the electric machine comprises: a torque converter drive plate coupled to the rotor drive hub; and a torque converter coupled to the torque converter drive plate.

According to one embodiment, assembling the torque converter includes welding portions of a torque converter housing to each other.

According to one embodiment, the invention is further characterized by aligning the torque converter drive plate with the rotor drive hub using a radial interference fit formed between the rotor spider and the torque converter drive plate.

According to one embodiment, clamping the rotor support to the plurality of stacked portions comprises mating a plurality of splines in the rotor support and the rotor drive hub.

According to the present invention, there is provided a power train system in a hybrid vehicle, the power train system having: an electric machine, the electric machine comprising: a rotor including a plurality of laminated rotor portions; a rotor support; and a rotor drive hub sandwiched between an axial face of the rotor frame and an axial face of the plurality of laminated rotor sections; a torque converter drive plate coupled to the rotor drive hub via an attachment apparatus; and a torque converter coupled to the torque converter drive plate.

According to one embodiment, the invention also features a splined interface formed between the rotor drive hub and the rotor support, wherein the splined interface includes a plurality of mating protrusions and recesses included in each of the rotor drive hub and the rotor support.

According to one embodiment, the torque converter is rotationally coupled to a drive wheel.

Claims

1. An electric machine, comprising:

a rotor including a plurality of laminated rotor portions;

a rotor support;

a rotor drive hub axially sandwiched between the rotor support and the plurality of stacked rotor portions;

a torque converter drive plate coupled to the rotor drive hub; and

a torque converter coupled to the torque converter drive plate.

2. The electric machine of claim 1 further comprising a splined interface formed between the rotor drive hub and the rotor support.

3. The electric machine of claim 2, wherein the splined interface comprises a plurality of mating protrusions and recesses included in each of the rotor drive hub and the rotor bracket.

4. The electric machine of claim 2 wherein the torque converter drive plate is secured to the rotor drive hub at a location radially outward from the splined interface.

5. The electric machine of claim 1, further comprising a keyed interface formed between the rotor drive hub and the rotor support, wherein the keyed interface includes a keyway that mates with a keyed protrusion.

6. The electric machine of claim 1, wherein the torque converter drive plate and the rotor drive hub are attached via a radial interference fit.

7. The electric machine of claim 1, wherein the electric machine is selectively rotationally coupled to an internal combustion engine and/or a torque converter.

8. The electric machine of claim 1 further comprising an end cap threadably connected to a first end of the rotor support and spaced apart from a second end of the rotor support coupled to the rotor drive hub.

9. The electric machine of claim 1 wherein the rotor support forms a continuous shape and includes support legs coupled to a rotor bearing.

10. The electric machine of claim 1, wherein the torque converter is coupled to a driveline.

11. The electric machine of claim 1, wherein the torque converter is rotationally coupled to a drive wheel.

12. A method for manufacturing an electric machine, comprising:

after assembling the torque converter, clamping a rotor bracket to a plurality of stacked portions in a rotor with a rotor drive hub axially positioned between a face of the rotor and a face of the rotor bracket;

wherein the motor includes:

a torque converter drive plate coupled to the rotor drive hub; and

a torque converter coupled to the torque converter drive plate.

13. The method of claim 12, wherein assembling the torque converter includes welding portions of a torque converter housing to each other.

14. The method of claim 12, further comprising aligning the torque converter drive plate with the rotor drive hub using a radial interference fit formed between the rotor spider and the torque converter drive plate.

15. The method of claim 12, wherein clamping the rotor support to the plurality of lamination portions comprises mating a plurality of splines in the rotor support and the rotor drive hub.